Laniatores

Kury, Adriano B., 2015, Opiliones are no longer the same — on suprafamilial groups in harvestmen (Arthropoda: Arachnida), Zootaxa 3925 (3), pp. 301-340 : 316-323

Phylogeny of Laniatores

The armored harvestmen ( Laniatores ) are here presented in more detail, separated from the rest of the Opiliones . In Figs. 12 to 19, the relevant hypotheses found in the literature concerning the branching pattern of the Laniatores are presented. The six following genera are here used to represent the major groups of Laniatores as currently understood: Erebomaster (for the Travunioidea s.s.), Equitius (for the Triaenonychoidea), Synthetonychia (for the Synthetonychiidae ), Gnomulus (for the Sandokanidae / Oncopodidae , consistently deemed to hold a special position), Phalangodes and Gonyleptes . See Table 4 for details.

The monophyly of this suborder has not been challenged since Perty (1833), who ranked the Cosmetidae together with the Eupnoi.

Hypothesis L1 ( Fig. 12 ) was prevalent by the end of 19th century. The young Triaenonychidae and Oncopodidae did not have yet a separate placement, and the Cladonychiidae were not yet recognized, its species being merged along with Oncopodidae in the Phalangodidae .

Hypothesis L2 ( Fig. 13 ) represented a major step forward, when Loman (1901; 1902) separated the Triaenonychidae as “sister” (a coordinate group) to the other Laniatores , calling it suborder Insidiatores. An expanded usage of the Insidiatores was later recovered by Kury (2003), also including Erebomaster , although formally this is not Loman’s original concept. Pocock (1902), in spite of his critics, followed this arrangement. Loman (1901) also separated Gnomulus from the Phalangodidae .

Hypothesis L3 ( Fig. 14 ) was a further refinement by Loman (1903), who created the names Sterrhonoti (for the Sandokanidae , then called Oncopodidae ) and Camptonoti (for the rest of his Laniatores ). Setting the Sandokanidae apart proved to be very popular, persisting in the literature for many decades. In the 1920s and early 1930s, a subdivision of the Laniatores became out of fashion. The families were simply listed as coordinate categories (e.g., Roewer 1923).

Hypothesis L4 ( Fig. 15 ): a major breakthrough happened in the mid-1930s, when Hadži (1935) recognized the close relationship between the southern hemisphere Triaenonychidae and the European Cladonychiinae. This group was later resurrected as Travunioidea ( Erebomaster + Equitius + Synthetonychia ) by Kratochvíl (1958) and as an “expanded” Insidiatores by Kury (2003), but it is currently widely regarded as a paraphylum. Kratochvíl (1958) put all remaining Laniatores as a monophylum (a hitherto unchallenged hypothesis, which he called “Oncopodoidea” and was later named Grassatores by Kury). Kratochvíl also combined Hadži’s group with Mello- Leitão’s special placement for Oncopodidae as sister group of the other Grassatores. Martens (1980) conserved exactly this arrangement, which also appeared in the combined molecular + morphological analyses by Giribet et al. (1999; 2002). This hypothesis was in the second half of the 20th century and at the turn of 21st century.

Hypothesis L5 ( Fig. 16 ): Mello-Leitão (1944) led to an extreme version of Loman’s (1903) attempt to segregate the Oncopodidae and put it at the base of his tree of “oculariate” Laniatores . Hadži’s component Erebomaster + Equitius is ever present, although nested a node above. Šilhavý (1961), who seemed to hold Mello- Leitão’s views in high regard (see, for instance, Šilhavý 1973), followed this scheme, naming the Sandokanidae (then Oncopodidae ) as Oncopodomorphi and all non-oncopodid Laniatores as Gonyleptomorphi. Bristowe (1976) did the same, separating the Sandokanidae from the rest, establishing a monofamilial suborder Oncopodines vs. the Laniatores s.s. .

Hypothesis L6 ( Fig. 17 ): Shultz elaborated morphological ( Shultz 1998) and molecular phylogenetic analyses ( Shultz & Regier 2001) that agreed with the notion ( Dumitrescu 1976 and Kury 1993) that the “expanded” Insidiatores were diphyletic. However, the branching pattern obtained was different from Kury-Dumitrescu scheme.

Hypothesis L7 ( Fig. 18 ): supported by Kury (2002), Giribet & Kury (2007) and Mendes (2009), also has the Travunioidea and Triaenonychoidea as two clades, but with the sister group sequence inverted in relation to hypothesis O 8. The special position for Sandokanidae is also refuted by this hypothesis; this taxon appears nested within the Grassatores.

Hypothesis L8 ( Fig. 19 ): finally Giribet and collaborators (2010) and Sharma & Giribet (2011) in a molecular analysis also did not recover the “expanded” Insidiatores in full. They also found Sandokanidae nested within Grassatores, although in a different position from hypothesis L7. The need is clear to do a total evidence analysis to reconcile the molecular with the morphological view.

Figures

FIGURE 12. Hypothesis L 1 of phylogeny of the Laniatores (Simon 1879). The lineages which would cause greater disturbance in the future were still dormant inside the Phalangodidae. Karsch (1880) and Sørensen (1886) kept basically the same pattern.

FIGURE 13. Hypothesis L 2 of phylogeny of the Laniatores (Loman 1901; 1902). This author proposed a sharp separation between the Triaenonychidae (which he called Insidiatores, here represented by Equitius) against all other Laniatores (which he called simply Laniatores [sensu stricto] and here called Lomaniatores). Pocock (1902) followed this hypothesis of phylogeny. The term Insidiatores was later reused in a broader sense.

FIGURE 14. Hypothesis L 3 of phylogeny of the Laniatores (Loman 1903). Only two years after creating the Insidiatores, Loman (1903) separated the Oncopodidae (which he called Sterrhonoti, here represented by Gnomulus) against the other Laniatores sensu stricto, called Camptonoti. This hypothesis lost support with the removal of the Cladonychiidae (here represented by Erebomaster) from the Phalangodidae by Briggs (1969).

FIGURE 15. Hypothesis L 4 of phylogeny of the Laniatores Kratochvíl (1958). After the work of Forster (1954), who created the Synthetonychiidae, this family went straight into the vicinity of the Triaenonychidae in the views of all most authors. Kratochvíl proposed a symmetrical arrangement of the groups we now know as Insidiatores versus Grassatores (then respectively called Travunioidea and Oncopodoidea). The morphological cladistic analysis by Martens (1980) recovered this arrangement, as well as both combined analyses by Giribet et al. (1999; 2002). Kury in his catalogue (2003) resurrected and expanded the original concept of Loman’s Insidiatores, using this name for the same clade recognized by Kratochvíl as Travunioidea.

FIGURE 16. Hypothesis L 5 of phylogeny of the Laniatores Šilhavý (1961). Šilhavý recognized the Travunioidea of Kratochvíl (here marked as “ Insidiatores ”, in blue) and made a change contraposing Oncopodidae against all other Laniatores, which has been anticipated by Mello-Leitão (1944), who had produced a surprisingly similar phylogeny (the famous cactus). This arrangement was conserved by Bristowe (1976).

FIGURE 17. Hypothesis L 6 of phylogeny of the Laniatores (Shultz 1998). Shultz morphological analysis (1998) and Shultz & Regier molecular analysis (2001) made a scarce sample of the Laniatores. The Insidiatores were dismantled, but the position of Synthetonychia was not made explicit, by not having been used in the analyses. The proximity of the Travuniidae with the Grassatores resembled Loman’s view of the Laniatores.

FIGURE 18. Hypothesis L 7 of phylogeny of the Laniatores (Kury 2002). A series of morphological studies—Kury (2002, morph), Giribet & Kury (2007, morph) and Mendes (2009, morph) — also favored the dismantlement of the Insidiatores, but joining the Triaenonychidae with the Grassatores. The new name Tricospilata is here proposed for this clade.

FIGURE 19. Hypothesis L 8 of phylogeny of the Laniatores (Giribet et al. 2010, mol). Grassatores remained firm, and the Insidiatores were dismantled, but in a novel way: the Synthetonychiidae were for the first time considered sister group to the other Laniatores. This result has been repeated by Sharma & Giribet (2011, mol). The new name Eulaniatores is proposed here to identify this clade, frontally conflicting with the Tricospilata concept illustrated in Fig. 18.